Today the U.S. Food and Drug Administration ordered three manufacturers of temporomandibular joint (TMJ) implants to conduct postmarket surveillance studies to determine the length of time before the implants are removed or replaced due to pain or other reasons.

The TMJ connects the lower jaw (mandible) to the temporal bone in the skull. A person may have an implant to replace the socket in the temporal bone or the rounded edge of the lower jaw that glides in the temporal bone socket because of an injury, arthritis, physical abnormality, or lost mobility.

The three manufacturers, TMJ Solutions, TMJ Medical, and Biomet Microfixation, make all of the currently approved TMJ devices marketed in the United States. The companies will have 30 days to submit a study plan which will need to be approved by the agency before any postmarket studies can begin.

TMJ implants also can be used to treat temporomandibular disorder (TMD) that has not responded to more conservative treatments such as limiting jaw movement, soft diet, jaw splint or adjustments, medicine to reduce pain, or physical therapy.

The FDA analyzed TMJ implant-related adverse event reports submitted between April 30, 2004 and Aug. 17, 2010. The analysis described a substantial number of patients who had implants replaced within three years or less after implantation because of extreme pain. This is considerably shorter than the expected minimum five-year life span of the device, based on premarket mechanical testing.

The FDA is not recommending any changes on use of the implants. The agency may revise its recommendations or issue other recommendations after reviewing additional clinical data from the studies. Patients who have or are considering a TMJ implant should consult with their health care professional.

TMJ implant manufacturers were required to collect postmarket data on their implants as part of the approval process. However, the data collected did not adequately address the timing or reasons for replacement, and the studies lost contact over the years with many of the enrolled patients.

The TMJ implant postmarket surveillance studies must address the following:

Time between initial implant and removal/replacement

Association between patient diagnosis and the timeframe between implant and removal/replacement

For replacement implants, the time between implant and subsequent removal/replacement

Reasons for removal/replacement of the implant

Associations between patient demographic and clinical data and the need or removal/replacement

Assessment of devices that have been removed from patients

As part of its review, the FDA will consider whether labeling changes, additional preclinical and clinical testing requirements, or other regulatory actions are necessary for these devices.